JPH05228731A - Positioning device for gear blank - Google Patents

Abstract

PURPOSE:To improve machining accuracy for instance in lathe-turning a ring gear, molded by forging. CONSTITUTION:A fixed clamper 4 which is freely rotated by a rotating-driving shaft 2 is provided with an annular projecting part 4a, and its outer peripheral part at an upper end is provided with a tapered face, and the periphery of the annular projecting part is provided with a collet chuck 10, whose periphery is provided with a tooth profile receiving member 6 energized upward by an energizing member 5, and the toothed part of ring gear blank W is engaged with receiving teeth provided on the upper face of the member 6. The ring gear raw material is pressedly clamped by an upper clamper 11, and the oblique face of the tooth end part on the bore side of the ring gear blank W is engaged with the tapered face of the fixed clamper 4 through the collet chuck 10 to centripetally adjust the ring gear blank W.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a positioning device for improving the processing accuracy when a forged ring gear is raced.

[0002]

2. Description of the Related Art Conventionally, a method of forming a ring gear such as a vehicle differential gear by forging is known. In this method, a gear material is formed from a billet by hot or cold forging, and unnecessary portions such as the bottom surface or side surfaces of the gear material except for the tooth portion are cut off by lace processing, and the tooth surface is polished to obtain a desired shape. I am trying to get the ring gear. Therefore, the gear material to be forged is formed to be larger than the final product shape by considering the grinding allowance and the polishing allowance.

[0003]

By the way, when the gear material after forging is race-processed, in the conventional case, for example, the gear material is simply sandwiched between the clamping devices of the heads of lathes, positioned, and processed while rotating. Therefore, there is a problem that the roundness of the gear and the thickness width of the gear cannot be managed well.

[0004]

In order to solve such a problem, the present invention provides a positioning device for race machining for clamping a gear material having a tapered tooth end surface on the inner diameter side of a ring gear or the like. That is, the fixed clamper having a tapered surface having substantially the same shape as the inner diameter side tooth end surface of the gear material and the gear material mounted on the fixed clamper are pressed from above and can be rotated around the central axis together with the fixed clamper. An upper clamper and a tooth profile receiving member that engages with the tooth portion of the gear material to regulate the gear material in the rotational direction, and the inner diameter side tooth end surface of the gear material and the tapered surface of the fixed clamper are provided on the outer periphery of the fixed clamper. A collet chuck that is clamped by is provided.

[0005]

By aligning the tooth end surface of the gear material on the inner diameter side with the tapered surface of the fixed clamper through the collet chuck, the center position of the gear material is accurately determined and the machining accuracy is improved.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A gear material positioning device of the present invention will be described with reference to the accompanying drawings. 1 is a longitudinal sectional view of a main part of the positioning device, FIG. 2 is a plan view of a fixed clamper, FIG. 3 is a perspective view of a collet chuck, FIG. 4 is a partially enlarged view of FIG.
FIG. 6 is an explanatory diagram of a ring gear material.

The positioning device of the present invention is used, for example, in the race processing of a ring gear which is a component of a differential device of a vehicle, and the ring gear is formed by forging.

Then, as shown in FIG. 5, the ring gear material W as a gear material is a crown gear having curved tooth traces, and an inner diameter side end surface of each tooth Wt is inclined to form an inclined surface s. Has been done. Further, an overhanging portion Wh that is cut off as an unnecessary portion in the subsequent process is formed on the inner peripheral portion thereof.

As shown in FIG. 1, the positioning device 1 is provided with a fixed clamper 4 fixed to a rotary drive shaft 2 via a holder member 3, and a fixed clamper 4 provided on the fixed clamper 4 and moved upward by a biasing member 5. A tooth-shaped receiving member 6 that is biased,
The tooth profile receiving member 6 is formed in a cylindrical shape and is provided around the annular protrusion 4 a of the fixed clamper 4.

A large-diameter cylindrical guide member 8 is provided further outside along the outer circumference of the tooth profile receiving member 6 and is fixed to the fixed clamper 4 by a plurality of bolts 7, and the inner surface is engaged. The portion 8a is engaged with the engaging portion 6a of the tooth profile receiving member 6 to guide the vertical movement of the tooth profile receiving member 6 and regulate the rotation.

Further, on the upper surface of the tooth profile receiving member 6, as shown in FIG.
As shown in FIG. 5, the tooth 6b is provided which can mesh with the tooth Wt of the ring gear material W.
May be provided over the entire circumference along the circumference or may be locally provided at a plurality of locations. Then, the tooth portions of the ring gear material W are faced and meshed on the receiving teeth 6b for positioning, but it is better to have the receiving teeth 6b at a plurality of positions in terms of positioning accuracy.

By the way, the annular protrusion 4 of the fixed clamper 4
As shown in FIG. 4, a has an upper end protruding higher than the upper end position of the holder member 3, and a tapered upper end tapered surface t is provided on the protruding outer peripheral surface. And this tapered surface t
Are substantially the same shape along the inclined surface s on the inner diameter side of the ring gear material W.

The inner surface side of the annular projection 4a is also gently inclined to project the central part, and a part of the lower surface of the ring gear material W placed above by the projection f is radially formed. I try to support it with a narrow circle.

A sleeve-shaped collet chuck 10 is provided between the annular projection 4a and the tooth-shaped receiving member 6.

As shown in FIG. 3, the collet chuck 10 has a sleeve-shaped upper end that is bent inward to form a bent portion 10a, and a cut c having a predetermined length extends downward from the bent portion 10a. It is provided at a plurality of locations along the direction.

The bent portion 10a is a ring gear material W.
Is bent at an angle slightly shallower than the inclination of the inclined surface s on the inner diameter side.

Therefore, the collet chuck 10 is fitted and fixed in the annular protrusion 4a of the fixed clamper 4, but the bent portion 10a at the upper end is normally in the annular protrusion 4a.
The taper surface t is slightly lifted up.

Above the receiving jig side, an upper clamper 11 as shown in FIG. 1 is provided. The upper clamper 11 can move up and down, and when the ring gear material W is sandwiched between the fixed clamper 4 and the fixed clamper 4 in a manner to be described later, the upper clamper 11 and the fixed clamper 4 are rotatable about a vertical central axis.

The upper clamper 11 is provided with a pressing portion 11a having a diameter smaller than the inner diameter of the ring gear material W so that the upper surface of the protruding portion Wh of the ring gear material W can be pressed.

The operation of the positioning device 1 having the above structure will be described.

The ring gear material W which has been forged and formed is placed on the tooth profile receiving member 6. At this time, the upper clamper 11
Is located above, and the tooth profile receiving member 6 is also lifted up by the biasing member 5 and is located higher than the position shown in FIG.

The tooth portion of the ring gear material W is directed downward and meshes with the receiving tooth 6b of the tooth profile receiving member 6.

Next, the upper clamper 11 descends and presses the upper surface of the protruding portion Wh of the ring gear material W downward. Therefore, the ring gear material W and the tooth profile receiving member 6 are both pushed downward against the biasing member 5.

During this descent, the inclined surface s of the ring gear material W shown in FIG.
0a, and then the bent portion 10 that has been separated
The a and the taper surface t of the fixed clamper 4 come into contact with each other, so that the ring gear material W is centered and aligned. Further, since the inner diameter side tooth end surface of the ring gear material W is a portion with high accuracy,
The precision of the perfect circle adjustment of the ring gear material W is also high.

Finally, in the state where the perfect circle is adjusted, the lower surface of the overhanging portion Wh of the ring gear material W abuts on the projecting portion f at the upper end of the annular projecting portion 4a. Since the support is in a state close to line contact, the perfect circle matching function during rotation is not impaired. Also, the collet chuck 10
The ring gear material W is securely clamped by the elasticity of the bent portion 10a.

When the rotary drive shaft 2 is driven in this state, the ring gear material W is fixed to the fixed clamper 4 and the upper clamper 1.
1, the bottom surface and the side surface are race-processed up to the position of the chain line shown in FIG. 1 by the cutting tool 12, but since the perfect circle adjustment is accurate, the processing accuracy is increased. That is, the roundness, the thickness of the gear, etc. are accurate. The overhang W on the inner surface side
The removal of h and the inner surface grinding are processed in the subsequent steps.

Further, the height adjustment and processing amount of the fixed clamper 4 are set in advance, and the subsequent adjustment is also possible.

[0028]

As described above, in the gear material positioning device of the present invention, when the gear material having the tapered tooth end surface on the inner diameter side is race-processed, the tapered portion of the inner diameter side tooth end surface which is molded with normal accuracy is formed. Since the positioning is carried out to enhance the centripetal function, it is possible to improve the machining accuracy such as the roundness and thickness of the gear.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a main part of a positioning device.

FIG. 2 is a plan view of a fixed clamper.

FIG. 3 is a perspective view of a collet chuck.

FIG. 4 is a partially enlarged view of FIG.

FIG. 5 is an explanatory diagram of ring gear material.

[Explanation of symbols]

 1 Positioning device 4 Fixed clamper 6 Tooth profile receiving member 10 Collet chuck 11 Upper clamper W Ring gear material Wt Teeth s Inclined surface t Tapered surface

Claims (1)

[Claims] 1. A positioning device for race machining for clamping a gear material having a tapered tooth end surface on the inner diameter side, wherein the device has a taper surface having substantially the same shape as the inner diameter side tooth end surface of the gear material. A clamper, an upper clamper that presses the gear material mounted on the fixed clamper from above and is rotatable around the central axis together with the fixed clamper, and engages with a tooth portion of the gear material to rotate the gear material in a rotating direction. And a tooth profile receiving member that regulates the gear shape, and a collet chuck that is sandwiched between the tooth end surface on the inner diameter side of the gear material and the tapered surface of the fixed clamper is provided on the outer periphery of the fixed clamper. ..